Unlike the original mod, which has a firing speed 3x faster than the gun turret, my mod is 2.4x faster. Here's why I made this change:

In the code, turrets have a ‘cooldown’ property that expresses how many ticks are between two shots. The gun turret has a cooldown of 6, which means it fires at a rate of 10/s (1s = 60 ticks).
The value of the original heavy gun turret is 2, giving it a firing speed of 30/s.

With shooting speed tech level 6, turrets have a bonus of +150%, or 2.5x their base speed. The gun turret therefore increases to 10 + 15 = 25/s.
The heavy gun turret should increase to 30 + 45 = 75/s. However, the game does not allow a cooldown value lower than 1 tick, so the turret is capped at 30 + 30 = 60/s.

By giving a base cooldown value of 2.5, or 24/s, once the bonus is at its maximum, the turret reaches 24 + 36 = 60/s.

This avoids a situation where one might wonder why the bonus does not apply as one would expect it to (expected at 75/s).
From a balancing perspective, this doesn't change much, given that the heavy gun turret is unlocked with advanced science packs and it's very likely that the shooting speed tech is already maxed out. This therefore won't change the value of 60/s.

i want to just add some stuff. People who install such mods are also using enemy mods or similar. Meaning there should at least be an option to get a "rebalanced" version.

Regarding that, the solution to bypass this 60/s is how the shotgun and similar work. Aka it still fires 60/s speed however each shot has more then 1 bullet. Meaning even if the bullets shot 2 at a time, even if the speed is still caped at 60, it will fire (cause damage) 120 worth of bullets in 1 second.

Hi

i want to just add some stuff. People who install such mods are also using enemy mods or similar. Meaning there should at least be an option to get a "rebalanced" version.

I'm not sure I understand what you're requesting. Could you clarify?

As for shooting speed, I don't think it needs to be increased too much. But I could add a setting to allow players to customize the damage dealt by turrets. That way, if the rate of fire is too slow for a player's liking, they can increase the damage to compensate.

Setting added in 1.3.0 :)